This invention relates to a fuel tank valve apparatus and particularly, to a fuel tank valve apparatus that is suitable for use with a fuel tank constructed of a polymeric material. Most particularly, this invention relates to a valve apparatus that is welded to a fuel tank to mount the valve assembly in a fixed position in an aperture formed in the fuel tank.
Mounting assemblies that are used to mount a venting valve assembly in a top wall of a fuel tank are known. See for example, U.S. Pat. No. 4,966,189 to Harris, which is incorporated herein by reference.
According to the present invention, a fuel tank valve apparatus is provided that includes a valve assembly that has a housing with a body portion, a flange coupled to the body portion, a retainer block, and a valve positioned to lie in the body portion. The retainer block extends away from the body portion spaced-apart from the flange. In addition, the fuel tank valve apparatus includes a retainer adapted to be coupled to an exterior surface of the fuel tank. The retainer includes a body portion defining a passageway sized to receive the body portion therein and a ring coupled to the body portion and extending into the passageway. The flange and retainer block of the housing cooperate with the body portion and the ring of the retainer respectively to couple the valve assembly and retainer together.
In preferred embodiments, the ring includes a fixed-end portion coupled to the body portion and a ramped free-end portion extending into the passageway. The free-end portion includes a series of tabs that are spaced-apart relative to one another. Each tab is formed to flex radically outwardly toward the body portion upon engaging an angled cam surface provided on one of the retainer blocks during insertion of the valve assembly downward through the passageway formed in the body portion of the retainer and the aperture formed in the fuel tank wall.
The valve assembly includes a cylindrical housing having an inlet at its bottom end and an annular mounting flange near its top end and an outlet portion coupled to the top end of the housing and formed to include a fuel vapor discharge tube. The valve assembly also includes four circumferentially spaced-apart retainer blocks and each retainer block includes a downwardly facing angled cam surface an upwardly facing retainer surface.
During insertion of the valve assembly into the fuel tank through the passageway formed in the body portion of the retainer and the aperture formed in the fuel tank wall (after welding the retainer in its mounted position on the fuel tank wall surrounding the aperture formed in the fuel tank wall), some of the flexible tabs on the ring coupled to the mounted retainer are cammed "out of the way" by the downwardly facing angled cam surface on the four retainer blocks to allow the valve assembly to be moved through the passageway formed in the body portion of the retainer to engage the annular mounting flange near the top end of the cylindrical housing against a top end of the welded retainer. At this point, the flexed tabs "snap back" to their original positions and engage against the upwardly facing retainer surfaces formed on the retainer blocks to retain the valve assembly in a mounted position in the retainer that is welded to the fuel tank.
Additional features of the present invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.